As wireless technologies evolve, devices using these technologies become smaller and less expensive while wireless features grow in their requirements for increased performance and functionality. As a result, there are needs for increased power densities in the RF components used to make wireless devices, particularly those used in high power applications such as RF power amplifiers; therefore, new semiconductor technologies are being developed to address these needs.
Gallium nitride (GaN) is a semiconductor technology that offers significantly higher power density over other technologies such as silicon lateral diffused metal oxide semiconductor (LDMOS) transistors, gallium arsenide hetero junction bipolar transistors (HBT) and pseudo-morphic high electron mobility transistors (pHEMT). GaN devices using native GaN substrates are expensive and not readily available; however, GaN devices can be fabricated by growing GaN epitaxy layers, aluminum gallium nitride (AlGaN) epitaxy layers, or silicon carbide (SiC) epitaxy layers on a donor substrate, such as aluminum nitride (AIN), silicon carbide (SiC), sapphire, or silicon (Si). Even by using donor substrates, GaN devices are more expensive than other semiconductor technologies, such as gallium arsenide (GaAs).
RF ICs are commonly produced as complete functional devices, which contain most of the components necessary to implement their desired functions including both active and passive components; however, newer technologies, such as GaN, may not have the mature suite of passive components with which to fabricate a complete functional RF IC. Accordingly, there is a need for an efficient and cost effective way to build RF ICs using GaN technology.